DiCaprio took to Facebook to express his condolences for his co-star, who died in her sleep Sunday at the age of 69.

"Darlene was the best acting mom I ever had the privilege of working alongside," DiCaprio wrote. "Her endearing personality and incredible talent will live on in the memories of those who knew her, and those who loved her work. My thoughts and prayers are with her family during this difficult time."

Cates' death was revealed by her sister, Sheri Cates Morgan, stating: ""It is with a bitter-sweet heart that we share that our precious wife, mother, and Gaga, Darlene Guthrie Cates, was called Home, somewhat unexpectedly, peacefully in her sleep Sunday morning, March 26th. We take comfort in knowing that she is no longer in pain and is in the arms of our Heavenly Father."

What's Eating Gilbert Grape was Cates' only major film role in her lifetime. Though she appeared in the occasional TV guest spot, fans will certainly remember her most for the 1993 film adaptation of the book of the same name. Peter Hedges, who wrote the book and the screenplay, saw Cates on an episode of Sally Jesse Raphael's syndicated talk show and offered her the role of Bonnie Grape in the film.

Cates received praise from both audiences and critics for her sensitive performance as a morbidly obese mother who struggles emotionally with the burden she has put on her family. DiCaprio also received acclaim for his performance as a teen with a developmental disability, earning him his first Oscar nomination in 1994.